Apparatus for drying thread by conduction



April 1948. R. w. STANLEY I 2,440,159

APYARATUS FOR DRYING THREAD BY CONDUCTIUN Filed Feb. 26, 1944 INVENTO E12 Wz/ ATTORNEY.

Patented Apr. 20, 1948 UNITED STATES PATENT OFFICE APPARATUS FOR DRYING THREAD BY CONDUOTION Application February 28, 19, Serial No. 523,985

2 Claims. 1

This invention relates to an improved method of and apparatus for drying and collecting filamentary material. More particularly, the invention is concerned with methods of drying and collecting filamentary material under a light but constant tension which permits freedom for uniform lengthwise contraction of the filamentary material during drying thereof.

According to the usual method of manufacturing artificial filamentary material, as by the viscose method, for example, the fiber-forming material is extruded into a coagulating and regenerating bath, from which it is withdrawn as a continuous thread and collected in the form of an annulus on the surface of a bobbin, or within a centrifugal bucket. The annulus is then sub- Jected to a number of after-treatments, such as desulfurizing, bleaching, etc., after which it is washed and dried in package form.

The drying of packages of filamentary material is generally accompanied by the development of a number of undesirable concomitants in that the different layers constituting the package tend to shrink unevenly which results in a thread of non-uniform denier.

Thread so dried is frequently found to possess varying residual shrinkage capacities along the length thereof, and varying dyeing amnities. so that knitted, woven, or otherwise fabricated materials manufactured therefrom are unsatisfactory.

One object of the present invention is to provide a method whereby running lengths of filamentary material are dried prior to collection thereof in package form and under substantially tensionless conditions or under a light but constant tension, so that it is permitted to shrink freely and unifttirmly throughout its length during the drying s ep.

Another object of the invention is to provide means for collecting dried running lengths of filamentary material and means for automatically adjusting the rate of collection to compensate for variations in tension of the material caused by the changing diameter of the package upon which the material is being wound or by any local variations in the capacity of the material to shrink under the given conditions.

According to the invention, filamentary material, preferably in the form of a bundle of filaments, twisted or untwisted, such as yarn, thread, etc., is continuously advanced through a drying zone, and thereafter passes through a loop to a winding device for collection in the form of a wound package. A tension responsive means is provided which comprises a tension responsive element in the loop formed in the material at the discharge end of the drying zone and a means associated with the tension responsive element 5 and with the driving means for the collecting device for varying the speed of the collecting device in response to a change in the position of the tension responsive element. The tension responsive means thus serves to maintain the loop in the dried material, insuring that a short length of the material remains suspended in the vicinity of the drying zone, and also serves to control, automatically, the speed at which the collecting device is driven. Any variations in the length of the suspended material are indicated by change in the position of the tension responsive element suspended in the loop, either upwardly or downwardly, which results in a corresponding decrease or increase in the speed at which the collecting go device is driven.

Under optimum conditions, the thread or the like advances over or through the drying zone. -through the loop, and to the collecting device under a light but constant tension which is main- 26 tained as near the zero point as possible and which is due to the weight of the short length of the material suspended in the vicinity of the drying zone, as a result of the loop formed therein, and the light weight of the tension responsive element thereon. Under certain conditions, however, the length of material suspended in the vicinity of the drying zone may be increased or decreased, with a resultant variation in the tension of the filamentary material passing through the drying zone. Thus, it may be increased due to an increase in the speed at which the filamentary material is advanced over or through the drying zone from a thread-advancing means. or it may be decreased due to the tendency of the material to shrink during drying, or as the result of an increase in the peripheral speed of the collecting device in response to a build-up of thread thereon.

In accordance with the invention, all such variations in the length of the filamentary material suspended in the vicinity of the drying zone, and thus of the tension of the material, are immediately automatically compensated for by a corresponding variation in the rate at which the dried filamentary material is collected. Thus undesired excess tension or slack of the material passing through the drying zone is immediately removed, with a resulting beneficial effect on the physical properties thereof. 6 The invention will be readily understood by 3 reference to the following detailed description when read in connection with the accompanying drawing. in which Figure 1 is an end view partly in section of a preferred embodiment of the invention: and

Figure 2 is a front elevation of a machine equipped with a plurality of units comprising drying and collecting devices according to the preferred embodiment of the invention.

In the drawing, i is a framework upon which is supported a tank 2 containing a coagulating and regenerating bath 2 of suitable composition. Viscose or other fiber-forming material is extruded into bath l, through a spinneret, in the form of a single filament or a plurality of filaments 4. The thread 4 is drawn from the bath by means of draw-off roller I, and is then passed to a thread-storing, thread-advancing device or reel I, through a trough l containing a suitable treating liquid. Thread-advancing, thread-storing means I may be driven at a speed such that the thread is given a stretch between it and drawoiI roller 5. On thread-advancing reel 1, the thread may be sprayed or bathed with a liquid or liquids from a pipe or a plurality of separate pipes extending across the spinning machine. such as pipes 9, 8'. having nomies or the like therein. such as shown at 8. l. The thread is then continuously forwarded over the smooth surface of a heating element H). which may be interioriy heated by any suitable means, and dried during its travel thereover. A tension responsive means is provided, having a tension responsive element such as pulley ll, preferably constructed of a light weight material such as Bakelite," under which the dried thread passes. after leaving the drying zone, and which is thus suspended in the loop formed in the material. After passing through the loop, the thread is advanced to the collecting device i2, through the traversing thread guide II.

The tension responsive means also includes an arm ll. one end of which is mounted on spindle I5, and the other end of which is secured for rotation with shaft It by collar ll. Shaft it which is supported on frame work I by bracket 24, also has mounted thereon a transverse arm forming two oppositely extending rods II and I0. Rod ll carries a screw-type adjustable balance weight 20. Rod i9 carries a pulley 2| which normally rests lightly upon an endless belt 22 which is supported by rollers 23, and which in turn rests upon pulley 2B which is rotatably mounted between bearings 21 and 28 on shaft 25,'in direct-drive relation with the collecting device H. The speed of the collecting device I2 is controlled by the pressure exerted by pulley II on belt 22. and the resulting pressure of belt 22 on pulley 28.

As the speed of collecting on device l2 tends to increase. because of increase in the diameter of the package. the length of material suspended in the vicinity of the drying zone tends to be shortened. Any such shortening will immediately cause pulley II to rise. actuating arm ll, which will in turn raise pulley 2! from belt 22, diminishing the pressure of the belt on pulley 26, thus decreasing the speed at which the collecting device I2 is driven, and automatically restoring the material suspended in the vicinity of the drying zone to its previous predetermined length.

n the other hand. if for any reason an undesirably large amount of slack occurs in the material suspended in the vicinity of the drying zone, pulley i I is lowered. actuating arm ll so as the undesired excess tension is automatically removed.

The supports 23 for endless belt 22 are rotatable, but otherwise fixed, and are preferably so positioned with respect to the tension responsive means that each of the individual drying and collecting means comprising one of a plurality of units of the machine may be independently adjusted without interference with any of the remaining units.

The invention affords a delicately responsive means for automatically and substantially continuously machining a light but constant tension on running lengths of filamentary material during travel thereof over the heating element and thus insures freedom for uniform shrinkage of the material throughout its entire length. Filamentary material thus dried possesses uniform residual shrinkage capacities along the length thereof, as well as uniform dye afilnities. and is especially desirable for the fabrication of textile goods of superior quality.

Instead of drying the thread or the like by passing it over the surface of an interiorly heated element, the thread may be dried by passing it through a heated enclosed chamber or by sub- .iecting it to a high frequency electric current induced longitudinally or horizontally thereof, after which the material is formed into a loop and collected as described above. The heating element shown has the advantage that high temperatures may be utilized. thus permitting rapid drying of the traveling filamentary material.

Numerous changes and modifications may be made in the process and apparatus herein described without departing from the spirit and scope of the invention, which is not to be limited except as defined by the appended claims.

I claim:

1. In an apparatus for drying filamentary material of indefinite length, a smooth stationary heated surface. means for continuously advancing the material at a substantially uniform rate of speed over and in contact with the heated surface through a path having a substantially straight undeviating portion which comprises the heated surface and a loop portion at the discharge end of the straight portion, means adjacent the end of the path for collecting the material in the form of a wound package, means for varying the speed of the collecting means, and a tension responsive element in the loop for controlling the speed varying means and maintaining the length of the material moving freely in the straight and loop portions of the path substantially constant to permit free uniform lengthwise contraction of the material during drying.

2. In an apparatus for drying filamentary material of indefinite length, a smooth, stationary heated surface, means for continuously advancing the material at a substantially uniform rate of speed over and in contact with the heated surface through a path having a substantially straight undeviating portion which comprises the heated surface and a loop portion at the discharge end of the straight portion, means adjacent the end of the path for collecting the material in the form of a wound package, means for varying the 5 speed of the collecting means, and a tension responslve element suspended in the loop and as- 6 om'mn sums PATENTS Number Name Date soclated with 15116 Sp d 7 18 111 (50116 133 1135 w t m 21 191 latlng the speed of tha 00 185!!! m m with the 1 543 3 8 c m June 23 1925 length of the mEtCl'll-l XDDVIDR fuel? in the I 1545 3 c July 14 1925 st aig t 1111 P of the m to 3329354 c m p n 4 193 permit free M01111 lensthwise wn m 0! 2 0 4 1 9 Buuord June 15 937 the material 2,ooo,as2 Hermann Aug. 17, 1931 RICHARD BTAW- 2,141,421 Bendz Feb. 14, man 2,117,541 Stlenen Oct. 24, 1039 REFERENCES mm 2,248,408 Fryer July 8,1041 references are of record in the 2,283,699 Richardson May 19, 1942 111: i g ft ent: 2,301,242 Butterworth, J12, et a1. Nov. 10. 1942 Certificate of Correction Patent No.- 2,440,159.- April 20, 1948.

RICHARD W. STANLEY It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Column 1, lines 1 and 2, strike out the words method of and; column 4, line 19, for machining read maintaining; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofl'ice.

Signed and sealed this 22nd day of June, A. D. 1948.

. [IIAL] THOMAS F. MURPHY,

Alu'atamt Uomme'uiomr of Patents.

5 speed of the collecting means, and a tension re- 6 om'mn sures rs'rsm'rs sponslve element suspended in the loop and asnumber me an sedated with 16 speed 7 18 me (50113 1 2 735 wh t m 21 191 latlng the speed Of the eollectinl means h t e 1 543 3 c m June a 1925 length of the material movln: freely in the 5 1545 3 c July 4 1925 aig t 1136 End P of the m to 3329 35 c m p n 4, 193 permit free uniform lengthwise cont 2 0 4 189 Buuord June 15 937 the material 2,oso,as2 Hermann Aug. 17, 1931 RICHARD 2,141,421 Bendz Feb. 14, 1039 2,117,541 Stlenen Oct. 24, 1039 REFERENCES mm 2,248,408 Fryer July 3, 1041 r rerences are of record in the 2,283, 99 Richgrdgon May 19, 1942 111: tfii ii ft ent 2,301,249 Butterworth. J12, et :1. Nov. 10. 1942 Certificate of Correction Patent No.- 2,440,159.- April 20, 1948.

RICHARD W. STANLEY It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows: Column 1, lines 1 and 2, strike out the words method of and; column 4, line 19, for machining read maintaining; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofl'ice.

Signed and sealed this 22nd day of June, A. D. 1948.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

